some faxes are not received by No answer (T.30 T1 timeout)

[hgmnetwork]

Hello, we have found that some faxes are not received and gives the following error

MODEM TIMEOUT: waiting for v.21 carrier
RECV FAX: No answer (T.30 T1 timeout)

Does anyone know how to fix it or because it happens?

I copy the log hylafax

Jun 10 12:34:56.05: [18754]: SESSION BEGIN 000043604
Jun 10 12:34:56.05: [18754]: HylaFAX (tm) Version 4.3.11
Jun 10 12:34:56.05: [18754]: CallID: "999999999" "999999999" "<NONE>" "s"
Jun 10 12:34:56.05: [18754]: MODEM set XON/XOFF/FLUSH: input ignored, output disabled
Jun 10 12:34:56.05: [18754]: <-- [4:ATA\r]
Jun 10 12:34:59.77: [18754]: --> [7]
Jun 10 12:34:59.77: [18754]: ANSWER: FAX CONNECTION DEVICE '/dev/ttyIAX69'
Jun 10 12:34:59.77: [18754]: STATE CHANGE: ANSWERING -> RECEIVING
Jun 10 12:34:59.77: [18754]: RECV FAX: begin
Jun 10 12:34:59.77: [18754]: <-- HDLC<33:FF C0 04 B5 00 AA 12 9E 36 86 62 82 1A 04 14 2E B6 94 04 6A A6 4E CE 96 F6 76 04 2C 74 CC 74 8C 8C>
Jun 10 12:34:59.77: [18754]: <-- data [33]
Jun 10 12:34:59.77: [18754]: <-- data [2]
Jun 10 12:35:00.75: [18754]: --> [7]
Jun 10 12:35:00.75: [18754]: <-- HDLC<23:FF C0 02 04 04 04 04 04 04 04 04 04 04 04 04 04 04 04 04 04 04 04 04>
Jun 10 12:35:00.75: [18754]: <-- data [23]
Jun 10 12:35:00.75: [18754]: <-- data [2]
Jun 10 12:35:01.50: [18754]: --> [7]
Jun 10 12:35:01.50: [18754]: <-- HDLC<13:FF C8 01 00 73 5F 23 01 FB C1 01 01 18>
Jun 10 12:35:01.50: [18754]: <-- data [13]
Jun 10 12:35:01.50: [18754]: <-- data [2]
Jun 10 12:35:02.10: [18754]: --> [2]
Jun 10 12:35:02.10: [18754]: <-- [9:AT+FRH=3\r]
Jun 10 12:35:09.10: [18754]: --> [0:]
Jun 10 12:35:09.10: [18754]: MODEM <Empty line>
Jun 10 12:35:09.10: [18754]: MODEM TIMEOUT: waiting for v.21 carrier
Jun 10 12:35:09.10: [18754]: <-- data [1]
Jun 10 12:35:09.11: [18754]: --> [2]
Jun 10 12:35:09.11: [18754]: DELAY 1500 ms
Jun 10 12:35:10.61: [18754]: <-- [9:AT+FTH=3\r]
Jun 10 12:35:10.61: [18754]: --> [7]
Jun 10 12:35:10.61: [18754]: <-- HDLC<33:FF C0 04 B5 00 AA 12 9E 36 86 62 82 1A 04 14 2E B6 94 04 6A A6 4E CE 96 F6 76 04 2C 74 CC 74 8C 8C>
Jun 10 12:35:10.61: [18754]: <-- data [33]
Jun 10 12:35:10.61: [18754]: <-- data [2]
Jun 10 12:35:12.41: [18754]: --> [7]
Jun 10 12:35:12.41: [18754]: <-- HDLC<23:FF C0 02 04 04 04 04 04 04 04 04 04 04 04 04 04 04 04 04 04 04 04 04>
Jun 10 12:35:12.41: [18754]: <-- data [23]
Jun 10 12:35:12.41: [18754]: <-- data [2]
Jun 10 12:35:13.15: [18754]: --> [7]
Jun 10 12:35:13.15: [18754]: <-- HDLC<13:FF C8 01 00 73 5F 23 01 FB C1 01 01 18>
Jun 10 12:35:13.15: [18754]: <-- data [13]
Jun 10 12:35:13.15: [18754]: <-- data [2]
Jun 10 12:35:13.75: [18754]: --> [2]
Jun 10 12:35:13.75: [18754]: <-- [9:AT+FRH=3\r]
Jun 10 12:35:20.75: [18754]: --> [0:]
Jun 10 12:35:20.75: [18754]: MODEM <Empty line>
Jun 10 12:35:20.75: [18754]: MODEM TIMEOUT: waiting for v.21 carrier
Jun 10 12:35:20.75: [18754]: <-- data [1]
Jun 10 12:35:20.76: [18754]: --> [2]
Jun 10 12:35:20.76: [18754]: DELAY 1500 ms
Jun 10 12:35:22.26: [18754]: <-- [9:AT+FTH=3\r]
Jun 10 12:35:22.28: [18754]: --> [7]
Jun 10 12:35:22.28: [18754]: <-- HDLC<33:FF C0 04 B5 00 AA 12 9E 36 86 62 82 1A 04 14 2E B6 94 04 6A A6 4E CE 96 F6 76 04 2C 74 CC 74 8C 8C>
Jun 10 12:35:22.28: [18754]: <-- data [33]
Jun 10 12:35:22.28: [18754]: <-- data [2]
Jun 10 12:35:24.09: [18754]: --> [7]
Jun 10 12:35:24.09: [18754]: <-- HDLC<23:FF C0 02 04 04 04 04 04 04 04 04 04 04 04 04 04 04 04 04 04 04 04 04>
Jun 10 12:35:24.09: [18754]: <-- data [23]
Jun 10 12:35:24.09: [18754]: <-- data [2]
Jun 10 12:35:24.83: [18754]: --> [7]
Jun 10 12:35:24.83: [18754]: <-- HDLC<13:FF C8 01 00 73 5F 23 01 FB C1 01 01 18>
Jun 10 12:35:24.83: [18754]: <-- data [13]
Jun 10 12:35:24.83: [18754]: <-- data [2]
Jun 10 12:35:25.43: [18754]: --> [2]
Jun 10 12:35:25.43: [18754]: <-- [9:AT+FRH=3\r]
Jun 10 12:35:32.43: [18754]: --> [0:]
Jun 10 12:35:32.43: [18754]: MODEM <Empty line>
Jun 10 12:35:32.43: [18754]: MODEM TIMEOUT: waiting for v.21 carrier
Jun 10 12:35:32.43: [18754]: <-- data [1]
Jun 10 12:35:32.43: [18754]: --> [2]
Jun 10 12:35:32.43: [18754]: DELAY 1500 ms
Jun 10 12:35:33.94: [18754]: <-- [9:AT+FTH=3\r]
Jun 10 12:35:33.96: [18754]: --> [7]
Jun 10 12:35:33.96: [18754]: <-- HDLC<33:FF C0 04 B5 00 AA 12 9E 36 86 62 82 1A 04 14 2E B6 94 04 6A A6 4E CE 96 F6 76 04 2C 74 CC 74 8C 8C>
Jun 10 12:35:33.96: [18754]: <-- data [33]
Jun 10 12:35:33.96: [18754]: <-- data [2]
Jun 10 12:35:35.76: [18754]: --> [7]
Jun 10 12:35:35.76: [18754]: <-- HDLC<23:FF C0 02 04 04 04 04 04 04 04 04 04 04 04 04 04 04 04 04 04 04 04 04>
Jun 10 12:35:35.76: [18754]: <-- data [23]
Jun 10 12:35:35.76: [18754]: <-- data [2]
Jun 10 12:35:36.50: [18754]: --> [7]
Jun 10 12:35:36.50: [18754]: <-- HDLC<13:FF C8 01 00 73 5F 23 01 FB C1 01 01 18>
Jun 10 12:35:36.50: [18754]: <-- data [13]
Jun 10 12:35:36.50: [18754]: <-- data [2]
Jun 10 12:35:37.10: [18754]: --> [2]
Jun 10 12:35:37.10: [18754]: <-- [9:AT+FRH=3\r]
Jun 10 12:35:44.10: [18754]: --> [0:]
Jun 10 12:35:44.10: [18754]: MODEM <Empty line>
Jun 10 12:35:44.10: [18754]: MODEM TIMEOUT: waiting for v.21 carrier
Jun 10 12:35:44.10: [18754]: <-- data [1]
Jun 10 12:35:44.11: [18754]: --> [2]
Jun 10 12:35:44.11: [18754]: RECV FAX: No answer (T.30 T1 timeout)
Jun 10 12:35:44.11: [18754]: RECV FAX: end
Jun 10 12:35:44.11: [18754]: SESSION END


thanksssss